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Full text of "The Cambridge Natural History"

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very marked feature, moreover, of the mammal's brain Is the
development of regular fissures upon its surface, which fissures
are only absent from OrnitJiorhynchus, various small Rodents,




FIGL 49.  Brain of Dog.   A, ventral ; B, dorsal ; C, lateral aspect.   B.ol, Olfactory lobe ,*
Or.ce* crura cerebri ; great longitudinal fissure ; //J7 J/JI1, lateral lobes of
cerebellum ; Hyp* hypophysis ; Med> spinal cord ; JV"//, medulla obloiigata ; Ify
pous Varolii ; VXf, cerebral henxispheres ; Wu, zniddle lobe (verniis) of cerebellum j
"/, cerebral nerves.    (From. Wiedersheim's Oomparative An

Bats, and Insect! vores, among living mammals. It is some-
times, but erroneously, said that the more complicated the
fissures of the brain are, the higher in intelligence and " zoological
position" is the possessor of that brain. Instances can un-
doubtedly be quoted to support such a view ; but they a:re